Safety switch device having stabilizing track and slot components

ABSTRACT

A safety switch device for preventing accidental firing of rockets in a rocket launcher by means of a switch that electrically isolates the rocket firing devices from a power input and another switch that grounds the rocket firing devices. The individual switches are simultaneously actuated from one switch position to another by a detachable pressure member, the presence of which member in the switch corresponds to a first predetermined circuit condition while the absence of this pressure member from the switch corresponds to a second predetermined circuit condition. The switch device includes a support member for the individual switches and a switch restraining member arranged to move with respect to the support member. A stabilizing track and a stabilizing slot are provided on the support and restraining members to stabilize the movement of the restraining member with respect to the support member.

United States Patent Modene SAFETY SWITCH DEVICE HAVING STABILIZING TRACK AND SLOT COMPONENTS Robert G. Modene, Glen Carbon, Ill.

Harvard Industries, Inc., Farmingdale, NJ.

Filed: June 14, 1971 Appl. No.: 152,776

Inventor:

Assignee:

Field of Search 89/1.8l4; 200/153 L, 153 LA References Cited UNITED STATES PATENTS 3/1972 Omohundro 200/153 LA X 10/1954 Carter ZOO/153 LA X 8/1953 Burrell et a]. 200/153 LA X Primary Examiner.lames R. Scott Assistant Examiner-William J. Smith Attorney, Agent, or Firm--John D. Pope, Ill

[5 7] ABSTRACT A safety switch device for preventing accidental firing of rockets in a rocket launcher by means of a switch that electrically isolates the rocket firing devices from a power input and another switch that grounds the rocket firing devices. The individual switches are simultaneously actuated from one switch position to another by a detachable pressure member, the presence of which member in the switch corresponds to a first predetermined circuit condition while the absence of this pressure member from the switch corresponds to a second predetermined circuit condition. The switch device includes a support member for the individual switches and a switch restraining member arranged to move with respect to the support member. A stabilizing track and a stabilizing slot are provided on the support and restraining members to stabilize the movement of the restraining member with respect to the support member.

9 Claims, 10 Drawing Figures SHEET 1 BF 2 lNVENTOR ROBERT G. MODENE ATTORNEY FATENTED R 2 I974 SHEEI 2 [IF 2 FIG. 2 FIGS 35 3 7& FIG. 7 f w 62 M 75 78 45 82 W M a as If (M -I "5 5 EI 50 Q T 6 5a 1 0 FIG. 9 7a 82 S 3 INTERVALOMETER J K I INPUT CONNECTOR L OUTPUT FIRING CIRCUITS f INTERVALOMETER 1 INPUT 50 CONNECTOR L 30 OUTPUT FIRING CIRCUITS INVENTOR ROBERT G. MODENE By W b; ?r.o 11r ATTORN EY SAFETY SWITCH DEVICE HAVING STABILIZING TRACK AND SLOT COMPONENTS This invention is directed to new and useful improvements in switches and more particularly to a safety device for preventing accidental firing of rockets in a rocket launcher.

Rocket launchers such as disclosed in US. Pat. No. 3,3 I 5,565 generally include a plurality of rockets individually packaged in respective rocket tubes, the tubes being clustered together in a bundle-like arrangement for attachment to the outer portion of an aircraft. Firing of the rockets in a rocket launcher is usually electrically actuated, the rocket firing devices being electrically connected to firing circuit control means inside the aircraft.

During attachment of the rocket launcher to the aircraft it is a desirable safety precaution to have the rocket firing device electrically grounded so that none of the rockets can be accidentally fired. One known circuit grounding device comprises a switch containing a resilient movable conductor and two fixed contact members. The movable conductor is normally biased toward one of the contacts corresponding to an ungrounded circuit position. The circuit grounding device also includes a biasing member that maintains the conductor member against the other contact corresponding to a grounded condition of the firing circuit. Thus when the rocket launcher is hoisted in place onto the aircraft, the biasing member in the circuit grounding device is arranged to ground the rocket firing devices so that none of the rockets can be accidentally fired.

When the airplane is ready for takeoff, the biasing member can be removed, permitting the resilient conductor to engage the contact corresponding to an ungrounded circuit condition, whereby the rocket firing devices are electrically connected to the firing circuit control means within the aircraft. One of the problems with this known circuit grounding device is that resiliency of the conducting member is affected by prevailing temperature conditions. Another problem is that inadequate performance of the switch can result if a foreign substance in the grounding device fixes itself upon one of the contacts or the conducting member.

Among the several objects of the present invention may be noted the provision of a novel safety switch; a novel safety switch device having a switch contact member that is substantially shielded from foreign substances; a novel safety switch device substantially insensitive to prevailing temperature conditions; a novel safety switch device having novel stabilizing means for guiding the movement of a switch-engaging member; a novel safety switch device which can be easily disassembled and reassembled; and a novel safety switch device incorporating more than one switch member, each of which can be simultaneously actuated. Other objects and features will be in part apparent and in part pointed out hereinafter.

The present invention relates to a novel safety switch device for placing rocket firing means in either a grounded or ungrounded condition and at the same time either isolating or connecting the rocket firing means to a power input. In one embodiment of the invention the safety switch device comprises two resilient pushbutton switches, one of which is normally open,

the other being normally closed, both these normal I switch positions defining a first circuit condition. The

pushbutton switches are supported in a support memher having a movable restraining member arranged to slide thereon toward and away from the pushbuttons. A housing encases the support member, switches and restraining member and includes an actuator opening leading to the restraining member. Actuating means for simultaneously placing both switches in their nonnormal positions to define a second circuit condition are disposed in the actuator opening and include a detachable pressure member arranged to bear against the movable restraining member. Insertion of the actuating means in the actuator opening causes the restraining member to move with respect to the support member toward the pushbuttons, such that the restraining member depresses the pushbuttons into their non-normal switch position. Stabilizing means for guiding movement of the restraining member with respect to the support member include complementary track and slot components, one of the components being on the restraining member, the other component being on the support member. Detachment of the actuating means from the housing causes the switches to return to their normal positions corresponding to the first circuit condition.

The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

FIG. 1 is an exploded perspective view of a safety switch device which incorporates one embodiment of the present invention;

FIG. 2 is a front sectional view of the structure of FIG. 1 assembled;

FIG. 3 is a sectional view thereof taken on the line 33 of FIG. 2;

FIG. 4 is a view similar to FIG. 3 with the actuating pin removed;

FIG. 5 is a bottom view of the restraining member of the present invention;

FIG. 6 is a right side view thereof;

FIG. 7 is atop view, partially shown in section, of the support member and pushbutton switches of the present invention;

FIG. 8 is a right side view of the support member with the pushbutton switches removed;

FIG. 9 is a simplified schematic wiring diagram of circuitry incorporating the present invention wherein the switches are in their non-normal positions due to insertion of the actuating pin; and

FIG. 10 illustrates the circuit of FIG. 9 wherein the switches are in their normal positions due to removal of the actuating pin. I 7

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Referring to the drawings for a detailed description of the present invention, a safety switch device incorporating one embodiment thereof is generally indicated by reference number 10. Safety switch device 10 comprises a generally rectangular housing 12 formed of any suitable material such as aluminum or an alloy thereof. Housing 12 includes a hollow casing portion 14 having a flange 16 extending outwardly therefrom. Flange 16 includes a curved lower surface 18 that conforms to a switch mounting surface 20 on the periphery l ll of a rocket launcher (not shown). An actuator opening 22 is molded into or drilled through opposite casing walls 24 and 26 of housing 12. A cylindrical arc recess 28 is provided in a side wall 30, which recess is aligned with and conforms to the curvature of opening 22. An actuating pressure member such as a cylindrical pin 32 having a pull-ring 33 at one end thereof is detachably inserted into opening 22 for location in cylindrical arc recess 28.

Safety switch device further includes a caplike restraining member 34 having opposite side walls 36 and 38 merging into a bearing wall 40. A roof surface 42 spans walls 36, 38 and 40 and is provided with an elongated stabilizing slot 44 approaching bearing wall 40. Switch device 10 also includes a generally rectangular support member 52 having a pair of pushbutton switches 48 and 50 held therein. Support member 52 is formed of any suitable rigid material such as aluminum or an alloy thereof and includes an elongated stabilizing track 84 formed to protrude from a surface 86 thereof. Support member 52 further includes a border flange 54 extending outwardly from the base thereof, which flange is provided with a key protrusion 56 for engagement with a complementary key recess 58. in housing 12.

Pushbutton switches 48, 50, each includes a barrel 60 with a reduced neck portion 62 having a resilient pushbutton 64 disposed therein. Switches 48, 50, are disposed in bores 68, 70, in support member 52, such that barrels 60 bear against a support member wall 76 and neck portions 62 and buttons 64 protrude outwardly from holes 72, 74, in support member wall 76. A protective boot 66 threadably secured to each neck 62 also serves the purpose of locking switches 48 and 50 to wall 76. Thus boots 66 serve the dual purpose of fixing the position of switches 48, 50, in support member 52 and also help to protectively seal buttons 64 from any outside elements. Pushbutton switches 48, 50, further include lead wires 78, 80, respectively, and a common wire 82 extending outwardly of support member 52 from barrels 60. Wires 78, 80, 82, are arranged to pass through a hole 83 provided in border flange 54.

A generally rectangular flexible insulating gasket 88 is disposed intermediate housing 12 and switch mounting surface 20. Gasket 88 is made of any suitable material such as rubber and includes a hole 90 in alignment with hole 83 of border flange 54. The component parts of switch device 10 are assembled in the order shown in FIG. 1 for attachment to mounting surface by fasteners 92 provided in fastener holes 94 at the corners of housing 12. Holes 96 are provided at the corners of gasket 88 to correspond with holes 94 in housing 12. The engagement of key protrusion 56 on flange 54 with key recess 58 in housing 12 insures proper disposition of support member 52 in housing 12.

In using switch device 10, wires 78, 80 and 82 of switches 48, 50, are connected to a circuit such as that shown in FIG. 9. Pushbutton switch 48, which is of the normally closed type, is connected in series with an input connector that leads to a power source (not shown). Pushbutton switch 50, which is of the normally open type, is connected across a rocket firing device such as an intervalometer and also across the output firing circuits that are fed by the intervalometer.

Prior to attaching a rocket launcher to an aircraft, pin 32 is inserted into opening 22 of housing 12 to engage bearing wall of movable restraining member 34. Pin 32 moves restraining member 34 against boots 66 and buttons 64 of pushbutton switches 48, 50, to depress both buttons 64 simultaneously and place switches 48, 50, in their non-normal position. Normally closed switch 48 is thus opened to isolate the input connector from the intervalometer and normally open switch 50 is closed to ground the intervalometer to the aircraft frame, for instance, thereby preventing operation of the intervalometer by any stray voltages. Under this arrangement the switch is also shielded from radar frequency interference.

It should be noted that as pin 32 is inserted into opening 22 there is a frictional force between pin 32 and bearing wall 40, which force tends to pivot restraining member 34 on support member 52. This pivoting effect can cause member 34 to bind on support member 52, possibly leading to a malfunction of switch device 10. This pivoting tendency of restraining member 34 is checked by the engagement of stabilizing track 84 of support member 52 with stabilizing slot 44 of member 34, thereby insuring a smooth guided movement of member 34 along member 52.

At any suitable time, such as when the aircraft is ready for takeoff, pin 32 can be manually removed from housing 12 by pulling on ring 33. The frictional pivoting effect of member 34 on member 52 when pin 32 is removed is similarly avoided by the continuous engagement of stabilizing track 84 in stabilizing slot 44.

Upon removal of pin 32, resilient pushbuttons 64 expand to their normal positions, moving restraining member 34 back to its unbiased position. This movement of member 34 is also smoothly guided by track 84 and stabilizing slot 44.

The wiring diagram, as shown in FIG. 10, corresponds to the ungrounded circuit condition that exists when pin 32 is removed and switches 48, 50, are restored to their normal positions. Switch 48, in its nor mally closed position, completes the circuit between the input connector and the intervalometer such that the intervalometer is essentially connected to firing circuit control means (not shown) within the aircraft. As switch 50 is returned to its normally open position the intervalometer is ungrounded.

It will be apparent to those skilled in the art that the grounding switch device is particularly adaptable for outdoor use and can operate consistently under extreme weather conditions as encountered throughout the world and is not affected by the usual airborne temperature conditions. Some advantages of the novel circuit grounding device that are evident from the foregoing description include a smoothly operating pinactuated switch which can be easily disassembled and reassembled.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

l. A safety switch device comprising resilient switch means normally disposed in a first switch position and movable to a second switch position, a support member for holding said switch means during movement of said switch means between said first and second switch positions, a channel-shaped restraining member slidably mounted on said support member and engageable with said switch means for moving said switch means from said first switch position to said second switch position, actuating means for moving said restraining member on said support member to place said switch means in said second switch position, and stabilizing means for stabilizing movement of said restraining member on said support member, said stabilizing means comprising an elongated track component projecting from one of said members, and an elongated slot component formed in the other said member, such that movement of said restraining member with respect to said support member is stabilized by cooperation of said track and slot components.

2. A safety switch device as claimed in claim 1 wherein said actuating means comprise a pressure member bearing against said restraining member, said device further including locating means for locating said pressure member against said restraining member.

3. A safety switch device as claimed in claim 2 wherein said pressure member is detachable from said locating means, detachment thereof causing said switch means to be placed in said first switch position.

4. A safety switch device as claimed in claim 3 wherein said locating means includes a frame encasing said switch means and having an opening therein for insertion of said pressure member to move said restraining member into engagement with said switch means thereby placing said switch means in said second switch position.

5. A safety switch device as claimed in claim 4 wherein said opening in said frame locates said pres sure member against said restraining member.

6. A safety switch device as claimed in claim 1 wherein said support member includes said elongated track protruding therefrom and said restraining means include said elongated slot in complementary engagement with said track to provide stabilized movement of said restraining means along said support member.

7. A safety switch device as claimed in claim 1 wherein said switch means comprise at least one pushbutton switch mounted to said support member, said device further including a frame encasing said switch means and said restraining member, said frame having an opening leading to said restraining member, said actuating means being detachably disposed in said opening for engagement with said restraining member.

8. A safety switch device as claimed in claim 7 wherein disposition of said actuating means in said opening places said pushbutton switch in said second switch position, detachment of said actuator from said frame causing said pushbutton switch to be placed in said first switch position.

9. A safety switch device as claimed in claim 7 wherein said track component is provided on said support member and said slot component is provided on said restraining member. 

1. A safety switch device comprising resilient switch means normally disposed in a first switch position and movable to a second switch position, a support member for holding said switch means during movement of said switch means between said first and second switch positions, a channel-shaped restraining member slidably mounted on said support member and engageable with said switch means for moving said switch means from said first switch position to said second switch position, actuating means for moving said restraining member on said support member to place said switch means in said second switch position, and stabilizing means for stabilizing movement of said restraining member on said support member, said stabilizing means comprising an elongated track component projecting from one of said members, and an elongated slot component formed in the other said member, such that movement of said restraining member with respect to said support member is stabilized by cooperation of said track and slot components.
 2. A safety switch device as claimed in claim 1 wherein said actuating means comprise a pressure member bearing against said restraining member, said device further including locating means for locating said pressure member against said restraining member.
 3. A safety switch device as claimed in claim 2 wherein said pressure member is detachable from said locating means, detachment thereof causIng said switch means to be placed in said first switch position.
 4. A safety switch device as claimed in claim 3 wherein said locating means includes a frame encasing said switch means and having an opening therein for insertion of said pressure member to move said restraining member into engagement with said switch means thereby placing said switch means in said second switch position.
 5. A safety switch device as claimed in claim 4 wherein said opening in said frame locates said pressure member against said restraining member.
 6. A safety switch device as claimed in claim 1 wherein said support member includes said elongated track protruding therefrom and said restraining means include said elongated slot in complementary engagement with said track to provide stabilized movement of said restraining means along said support member.
 7. A safety switch device as claimed in claim 1 wherein said switch means comprise at least one pushbutton switch mounted to said support member, said device further including a frame encasing said switch means and said restraining member, said frame having an opening leading to said restraining member, said actuating means being detachably disposed in said opening for engagement with said restraining member.
 8. A safety switch device as claimed in claim 7 wherein disposition of said actuating means in said opening places said pushbutton switch in said second switch position, detachment of said actuator from said frame causing said pushbutton switch to be placed in said first switch position.
 9. A safety switch device as claimed in claim 7 wherein said track component is provided on said support member and said slot component is provided on said restraining member. 